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arXiv · 1608.02362

A Natural origin for the LHCb anomalies

Eugenio Megias·Giuliano Panico·Oriol Pujolas·Mariano Quiros
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Abstract

The anomalies recently found by the LHCb collaboration in $B$-meson decays seem to point towards the existence of new physics coupled non-universally to muons and electrons. We show that a beyond-the-Standard-Model dynamics with these features naturally arises in models with a warped extra-dimension that aim to solve the electroweak Hierarchy Problem. The attractiveness of our set-up is the fact that the dynamics responsible for generating the flavor anomalies is automatically present, being provided by the massive Kaluza--Klein excitations of the electroweak gauge bosons. The flavor anomalies can be easily reproduced by assuming that the bottom and muon fields have a sizable amount of compositeness, while the electron is almost elementary. Interestingly enough, this framework correlates the flavor anomalies to a pattern of corrections in the electroweak observables and in flavor-changing processes. In particular the deviations in the bottom and muon couplings to the $Z$-boson and in $ΔF = 2$ flavor-changing observables are predicted to be close to the present experimental bounds, and thus potentially testable in near-future experiments.

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Eugenio Megias, Giuliano Panico, Oriol Pujolas, Mariano Quiros. 2017-06-21. A Natural origin for the LHCb anomalies. https://doi.org/10.1007/jhep09(2016)118

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